1. Field of the Invention
The invention is concerned with a method for gutting decapitated and undecapitated fish, in particular farmed fish, including the steps of opening the abdominal cavity with a circular blade with guide gouge, scraping out and aspirating the entrails which are then partially detached with a suction nozzle, opening the membrane of the blood kidney, aspirating blood and water with suction scrapers and extracting entrails and blood and water via suction pipes.
Furthermore, the invention concerns an apparatus, in particular for carrying out the method, essentially including a conveyor with at least one fish receptacle for receiving the fish to be processed and conveying it in the direction of the processing station, means arranged in the region of the conveyor for opening the abdominal cavity, for scraping out and aspirating the entrails, for completely opening the membrane of the blood kidney and for aspirating blood and water as well as for extracting entrails and blood and water from the abdominal cavity.
2. Description of Related Art
A method of this kind with a corresponding apparatus for slaughtering and gutting the fish is known from document DE 198 29 376. In the known method, a gouge moves into the anal opening and forms the cutting support for a circular blade which opens the abdominal wall of the fish in the longitudinal direction. So that the circular blade can pass out of the fish unhindered, the gouge is swung back at the end of the cut. Then a first suction nozzle with open suction opening moves into the abdominal cavity, a ball valve in the suction pipe being closed to build up partial pressure in the suction pipe. The ball valve opens at the earliest when the suction nozzle has reached the bottom of the abdominal cavity. The entrails are aspirated and at the end of the abdominal cavity in the region of the lateral fins the suction nozzle is closed by a slide valve, the entrails being cut off with a cutting edge arranged on the slide valve before the suction nozzle swings back and returns to its starting position. During the so-called basic travel of the suction nozzle on the main bone, a blade opens the membrane of the blood kidney from the ventral fins to the end of the abdominal cavity. A subsequent second tool opens the blood kidney in the rear region (from the anus to the ventral fins) and removes blood and water in this region. A further, subsequent, third tool cleans the front region of the abdominal cavity (from the ventral fins to the end of the abdominal cavity) of blood and water, overlapping with the previous tool. All three tools are connected to a central vacuum device which consists of a vacuum pump with a filter, a cyclone and pipes. Entrails, blood and water are separated from the air stream in the cyclone and continuously discharged from the latter by an eccentric spiral pump or the like. The known method and the known apparatus do however have the disadvantage that further use of the entrails is only limited or not possible at all because, amongst other things due to the high speed of transport in the pipes, the separating process and the discharge by means of the eccentric spiral pump, entrails, blood and water occur as a homogeneous pasty mass. The known apparatus further has the disadvantage that, to open the membrane of the blood kidney, the blade of the suction nozzle also slits the entrails open in the longitudinal direction, so that they may be damaged or blood and other fluids may escape from the blood kidney and the innards which can lead to decomposition thereof or contaminate the usable components.